Which of the following metallurgical process is not needed in order to extract Zn from `ZnCO_(3)`?

Options

A. Calcination
B. Roasting
C. Carbon reduction
D. Distillation.

Explanation

To extract zinc from zinc carbonate (ZnCO₃), which is also known as calamine, we need to follow a series of metallurgical processes. Here is a step-by-step breakdown of the processes involved and the one that is not needed:

### Step 1: Calcination
- **Process**: The first step involves heating the zinc carbonate (ZnCO₃) to decompose it into zinc oxide (ZnO) and carbon dioxide (CO₂).
- **Chemical Reaction**:
\[ \text{ZnCO}_3 \xrightarrow{\text{heat}} \text{ZnO} + \text{CO}_2 \uparrow \]
- **Explanation**: This process is called calcination and is specifically used for carbonate ores.

### Step 2: Reduction
- **Process**: The next step is to reduce the zinc oxide (ZnO) to zinc metal (Zn). This is typically done by heating zinc oxide in the presence of carbon.
- **Chemical Reaction**:
\[ \text{ZnO} + \text{C} \xrightarrow{\text{heat}} \text{Zn} + \text{CO}_2 \uparrow \]
- **Explanation**: Here, carbon acts as a reducing agent, removing the oxygen from zinc oxide to produce pure zinc.

### Step 3: Distillation
- **Process**: After obtaining zinc, the metal may contain impurities. To purify it, distillation is employed.
- **Explanation**: In distillation, the lower boiling point impurities are evaporated, leaving behind the higher boiling point zinc metal.

### Step 4: Roasting (Not Needed)
- **Process**: Roasting is a process used for sulfide ores, where the ore is heated in the presence of oxygen to convert it into an oxide.
- **Explanation**: Since we are dealing with zinc carbonate and not zinc sulfide (ZnS), roasting is not required in this process.

### Conclusion
The metallurgical process that is **not needed** to extract zinc from zinc carbonate (ZnCO₃) is **roasting**.

### Final Answer
**Roasting** is the metallurgical process that is not needed to extract zinc from zinc carbonate.

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